Means for aerial spraying



Jan. 29, 1952 w. E. RIPPER ETAL 2,583,334

MEANS FOR AERIAL SPRAYING Filed Jan. 18, 1947 s Sheets-Sheet 1 Jan. 29, 1952 Filed Jan. 18, 1947 w. E. RIPPER ETAL 2,583,884

MEANS FOR AERIAL SPRAYING 3 Sheets-Sheet 2 Jan. 29, 1952 w. E. RIPPER ETAL MEANS FOR AERIAL SPRAYING 8 Sheets-Sheet I5 Filed Jan. 18, 1947 m msu Patented Jan. 29, 1952 MEANS FOR AERIAL SPRAYING Walter Eugene Ripper, Harston, and Arthur Kennedy Dorman, Sawston, England, assignors to Pest Control Limited, Harston, England, a' British company Application January 18, 1947, Serial No. 722,944

In Great Britain January'30, 1946 3 Claims. (01. 244-436) This invention relates to an improvement in a method ofand means for aerial spraying.

In the co-pending application of the said Walter Eugene Ripper for Letters Patent, Serial No. 722,945, filed January 18, 1947, which matured into Patent No. 2,583,883 on January 29, 1952, a method of treating a crop with a spray medium is described which comprises dispersing said spray medium and introducing said dispersed spray medium into the rotor downwash of a helicopter flying over said crop, so that said spray medium reaches 'said crop beneath said helicopter.

The said application also describes means for aerial spraying comprising a helicopter, a conwash of at least one rotor.

- so that said spray medium reaches the said crop beneath said helicopter and is deflected forwards and upwards on to the underside of said crop.

Preferably the apparatus also includes a dosage regulator.

The liquid or dust to be sprayed can be brought to the point of release in ducts, either dispersed in air or water or in a vaporous form, or it can tainer for spray medium, means for dispersing be released from a position near to the centre of said spray medium, a dosage regulator, and means the rotor and have so much kinetic energy imfor introducing said dispersed spray medium into parted to it that it is only broken up into a fine the downwash of the helicopter rotor to ensure dispersion when it reaches the forward part of the prevention of a long swath, so that said spray the rotor downwash as, for example from a nummedium reaches the crop beneath said helicopter. her 0f forward p jec g J whereby the Stream In the said copending application it is pointed is broken up after a certain distance, this distance out that the downwash of the rotor of a helicopter being so calculated that this occurs when it resembles a funnel-shaped whirlwind in shape reaches the forward part of the rotor downwash. having a hollow cone full of eddies surrounded by One or more forwardly projecting spray booms a strong downward current originating from the carrying nozzles or spray bars may be used for .rotor. When the helicopter hovers, this downducting the material to be sprayed into the for- .wash hits the ground in a ring around the airward part of the rotor downwash. When a tricraft. This therefore produces what might proprotor helicopter is employed, use may be made of erly be described as an annular downwash which the forward part of the downwash of each of the confines the swath of distribution of the material two forward rotors. The helicopter may fly forthat is sprayed. wards, or backwards or sideways and it will be It has now been found that improved results understood that references herein to the forward are obtained by introducing the liquid or dust part of the machine or apparatus refer to the into the forward part of the rotor downwash only. forward part in the direction of travel. Thus if It had previously been thought that the whole a tri-rotor helicopter is flown tail foremost, with of the rotor downwash of a forwardly travelling the single rotor mounted in the tail leading, spray helicopter would be deflected to the rear on strikbooms projecting forwardly in the direction of ing the ground. From tests which have been flight may be used for introducing material into made it now appears that, when the helicopter the forward part of the downwash of each of the travels at a moderate velocity and low altitude, three rotors. the forward part of the rotor downwash on strik- Preferably the spray booms are made adjusting the ground is actually deflected forwards, and able for height in relation to the crop to be upwards, tending to produce a vortex. By introsprayed and the rotors. ducing the liquid or dust into this forward part In order that the invention may be well underof the rotor downwash it has been found possible stood three embodiments thereof will now be deto effect an improved coverage of crops and more scribed and illustrated with reference to the acparticularly of the under surfaces of the leaves companying drawings, the three figures of which or crops, and it is believed that this improved each show a plan view of one embodiment. result is due to the above-mentioned phenomenon. In these drawings, Fig. l is a top plan view of a Accordingly the present invention provides tri-rotor helicopter provided with the spraying means for aerial spraying comprising a helicopter, means arranged in accordance with the present said helicopter having at least one rotor, a coninvention; tainer for spray medium, means for dispersing Fig. 2 is a similar view, but of a one-rotor helisaid medium and means for introducing said discopter, part thereof being shown only in outline; persed medium into the forward part of the downand Fig. 3 is a top plan view, with duplicated parts access;

dust from a pump or compressor, not shown, and,v

deliver the liquid or dust with such velocity that" it is only broken up into a fine dispersiorrtwhena.

it reaches the forward part of the downwash ofthe rotors I. This construction,-as-showrriir'Fig ure 1, provides a structure in'whichithere-arelift-g ing rotors carried at the end"of"-the outriggers' rotating on vertical shafts passing through vertical rotor-hubs, and spray-dischargezmeans belowiv said rotors which are attached to and radiate-out wardly from the said hubs to a locus. which forwardly of the nose portion of helicopter.

In the embodimentillustrated in Fig. 2 an arcuate spray bar--5 is" disposed below the forward partof'the singlerotorfi-of a; helicopter.

The spray bar is carried by'a spray'boom comprising, cantilever "arms 7' rigidly securedto nuts 8 displaceable along screw-threaded spindles 9 when'the latter are rotated by-means'of'across shaft" Hi driving the screw-threaded" spindles through bevel gear I'i. The-liquid or-dust is introduced' into the forward part of the rotor downwash' by-meansnotshown, comprising a pump or compressor, a dosage regulator; flexible tubing leadingtothe-spray bar and nozzles formed in the spray" bar; The spray-boom 'm-a-y be adjustedf'or-height by rotationof the cross shaftIIl.

In the' embodimentillustrated 'in Fig: 3; a trirotor helicopter-is provided with two forward A further spray boom comprising arms I? se- 4 cured to a rotatable cross shaftldand carrying a spraybar 19* ismoun-ted irrthe nose of the helicopter and maybe raised' and lowered by rotation of the cross shaft I8. The spraybars are provided with nozzles, not shown, and supplied with liquid or dust for introduction into the forward part of the rotor downwash by means (not shown) as in Fig. 2.

We claim:

1.1 helicopter adaptedrfortth'e .efficient spraying of insecticides and the like which comprises the combination of a fuselage having a frontal nose portion, Outriggers connected to said fuse- 1ag@':-a;1 1:d; extending outwardly and forwardly thereof, lifting rotors carried at the end of said outriggers rotating-on vertical shafts passing throughyertiical rotor-hubs, and spray-discharge meansbeldwsaid rotors attached to and radiating outwardly from said hubs to a locus forwardlyof said! nose portion.

2'. A helicopter as claimed in claim 1 in which the-,spray-discharge means radiating from said hubs are in the form of cantilever arms supporting arcuate spray-bars 3.- A helicopter as claimed in claim" 1 having additional spray-discharge means attached? to and extending forwardly ol 'the'nose portion of the fuselage of the helicopter:

WALTER'EUGENE ARTHUR" KENNEDY DDRMAN REFERENCE 8' 7 CITED The vfollowing,references areiof. recordainiithe fileoi, this patent UNITED STATESesPAI-ENTS:

OTHER REFERENCES.

Articlev American: Helicop ter, 7 Aug: 1946, vol-.1 3, November;.:9;' pagesq28 and; 41'; published by; American. Helicopter: Magazine; .32 zEa-st: 57th St;NewzYorkafmNaYd 

